Chapter XI 
Internal Anatomy of Mosquitoes 
The Alimentary Canal 
The alimentary canal is specialized on account 
of the blood-sucking habits of the mosquito. It 
differs from many insects in not possessing any caecal 
diverticula of the mid-gut. It also differs in the 
possession of five malpighian tubules, these being in 
insects usually even in number (Fig. 38). 
The parts of the alimentary canal are as follows :— 
The mouth \ 
The pharynx with pumping organ [The fore- 
The oesophagus 
The oesophageal diverticula 
The homologue of the proventriculus 
The stomach (so-called) 
The pylorus 
The pyloric dilatation 
The ileum 
The colon 
The rectum with rectal papillae 
[ The hind- 
r g ut - 
The mouth, pharynx, and oesophagus are ecto¬ 
dermal in origin, and both the mouth and pharynx 
are lined with chitin. The hind-gut is also ectodermal 
in origin ; it does not possess, however, any portion 
lined with chitin. The mid-gut is the true digestive 
portion of the tract. 
